Are hot tubs and saunas safe in pregnancy?

The NHS currently recommends that activities which might significantly increase the body’s core temperature are best avoided in pregnancy, especially in the first 12 weeks.

And Emma Lees-Laing, midwife for Tommy’s, the baby charity, also points out that "there’s a risk of fainting if you get too hot, so that's another reason we do advise pregnant women to avoid hot tubs and saunas".

That said, there is no clear evidence around the effects of over-heating on your pregnancy or unborn baby. And a new Australian study, published in the British Journal of Sports Medicine, suggests that the risks may be small.

“Health guidelines for pregnant women unanimously state that hot-water immersion or sauna use should be restricted due to the elevated risk of maternal hyperthermia and the consequent potential impact on fetal development," says lead researcher Dr Ollie Jay, Associate Professor in Exercise and Sports Science at the University of Sydney.

“However, our results suggest that heat stress risk is low.”

The researchers say their studies suggest that pregnant women could safely sit in hot baths (up to 40C) or hot/dry saunas (up to 70C and 15% relative humidity) for up to 20 minutes, irrespective of pregnancy stage.

But, the researchers conclude, more studies should be done before official advice is changed.

So, while it's worth knowing the official advice – and probably sticking to it until any changes are made – don't worry too much if you have used a sauna, hot tub, jacuzzi or steam room while pregnant. In Finland, where sauna use is widespread during pregnancy, there is no increased risk of abnormalities in the baby, according to the UK Teratology Information Service.

Mums in the MadeForMums community say

"I booked a weekend away for my husband's birthday and I was about 11 weeks. They had a hot tub and I asked MW if I could use it.

"She said it was ok as long as you don't have the water above 38°C. She said if you have a water birth this is the temperature they try and keep to (between 37-38°C) Me and my mate who were both pregnant went in and really enjoyed it. We only stayed in for about 20-30 mins at most." said member of our MadeForMums community Deborah.

Fellow MadeForMums community member Stacey said, "I asked Google and my midwife and was told by both that I could use them as long as it's not longer than 10-15minutes and my baby (due 11/17) loves it. He kicks happily and he is a healthy growing boy."

Read more:

• Is it safe to use a hot water bottle or heat pad whilst pregnant?
• Is it safe to have hot baths in pregnancy?